Dolmar PS-420 User Manual

Page 26

Checking the chain tension

The tension of the chain is correct if the chain rests against

the bottom side of the guide bar and can still be easily turned

by hand.
While doing so the chain brake must be released.
Check the chain tension frequently - new chains tend to get

longer during use!
When checking the chain tension the engine must be switched

off.
NOTE: It is recommended to use 2- chains alternatively.
In order to guarantee uniform wear of the guide bar the bar

should be turned over whenever replacing the chain.

Retensioning the saw chain

All that is necessary to retension the saw chain is to loosen the

quick tensioner (2) slightly as described under “Mounting the

guide bar and saw chain”.

Tension the chain as already described.

STOP

Engaging the chain brake (braking)

If the kickback is strong enough the sudden acceleration of the

guide bar combined with the inertia of the hand guard (1) will

automatically actuate the chain brake.
To engage the chain brake manually, simply push the hand

guard (1) forward (towards the tip of the saw) with your left

hand (arrow ).
Releasing the chain brake
Pull the hand guard (1) towards you (arrow 2) until you feel it

catch. The brake is now released.

Chain brake

The PS-50 and PS-420 comes with an inertia chain brake as

standard equipment. If kickback occurs due to contact of the

guide-bar tip with wood (see SAFETY PRECAUTIONS, page 6),

the chain brake will stop the chain through inertia if the kickback

is sufficiently strong.
The chain will stop within a fraction of a second.
The chain brake is installed to block the saw chain before

starting it and to stop it immediately in case of an emer-

gency.

IMPORTANT: NEVER run the saw with the chain brake acti-

vated (except for testing, see “Testing chain brake”)! Doing so

can very quickly cause extensive engine damage!

ALWAYS release the chain brake
before starting the work!